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If cos 2x =(sqrt2+1)( cos x-1/sqrt2),cos...

If `cos 2x =(sqrt2+1)( cos x-1/sqrt2),cos x!= 1/2`, then `x in I`

A

`{2 npi +- pi/3 : n in Z}`

B

`{2npi+- pi/6 : n in Z}`

C

`{2npi +- pi/2 : n in Z}`

D

`{2npi+- pi/4 : n in Z}`

Text Solution

Verified by Experts

The correct Answer is:
D
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